A door strike is used to protect the door frame from damage or marring as a result of being constantly struck by the latch bolt of the door lock every time the door is closed. While protecting the door frame from damage, the door strike also serves as a guide for the latch bolt to enter the hole in the door frame and thereby securely hold the door shut.
A simple door strike is usually made of metal with a bevelled striking edge, holes for screws so that it can be attached to the door frame and an opening or hole in its middle to accept the latch bolt of the lock. In the event the latch bolt cannot enter the hole in the door strike for any reason, then the door cannot be locked. In order to correct this problem, it is necessary to remove the strike from the door frame, notch out the opening in the door frame and replace the door strike. The door frame is then marred or damaged with an unnecessary opening and the screws used to attach the door strike to the door frame cannot securely grip the door frame because they line up with the old opening in the frame. The result of this "old fashioned" realignment is usually very time consuming and expensive.